{/* Copyright 2020 Adobe. All rights reserved.
This file is licensed to you under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License. You may obtain a copy
of the License at http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under
the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
OF ANY KIND, either express or implied. See the License for the specific language
governing permissions and limitations under the License. */}

import {Layout} from '@react-spectrum/docs';
export default Layout;

import docs from 'docs:react-aria-components';
import statelyDocs from 'docs:@react-stately/numberfield';
import {PropTable, HeaderInfo, TypeLink, PageDescription, StateTable, ContextTable} from '@react-spectrum/docs';
import styles from '@react-spectrum/docs/src/docs.css';
import packageData from 'react-aria-components/package.json';
import Anatomy from '@react-aria/numberfield/docs/anatomy.svg';
import ChevronRight from '@spectrum-icons/workflow/ChevronRight';
import {Divider} from '@react-spectrum/divider';
import {ExampleCard} from '@react-spectrum/docs/src/ExampleCard';
import Label from '@react-spectrum/docs/pages/assets/component-illustrations/Label.svg';
import Button from '@react-spectrum/docs/pages/assets/component-illustrations/ActionButton.svg';
import Input from '@react-spectrum/docs/pages/assets/component-illustrations/Input.svg';
import Form from '@react-spectrum/docs/pages/assets/component-illustrations/Form.svg';
import {StarterKits} from '@react-spectrum/docs/src/StarterKits';

---
category: Forms
keywords: [number field, input, form, aria]
type: component
---

# NumberField

<PageDescription>{docs.exports.NumberField.description}</PageDescription>

<HeaderInfo
  packageData={packageData}
  componentNames={['NumberField']}
  sourceData={[
    {type: 'W3C', url: 'https://www.w3.org/WAI/ARIA/apg/patterns/spinbutton/'}
  ]} />

## Example

```tsx example
import {NumberField, Label, Group, Input, Button} from 'react-aria-components';
import {Plus, Minus} from 'lucide-react';

<NumberField defaultValue={1024} minValue={0}>
  <Label>Width</Label>
  <Group>
    <Button slot="decrement"><Minus size={18} /></Button>
    <Input />
    <Button slot="increment"><Plus size={18} /></Button>
  </Group>
</NumberField>
```

<details>
  <summary style={{fontWeight: 'bold'}}><ChevronRight size="S" /> Show CSS</summary>

```css hidden
@import './Button.mdx' layer(button);
@import './Form.mdx' layer(form);
```

```css
@import "@react-aria/example-theme";

.react-aria-NumberField {
  margin-bottom: 8px;
  color: var(--text-color);

  .react-aria-Group {
    display: flex;
    width: fit-content;
    border-radius: 4px;

    &[data-focus-within] {
      outline: 1px solid var(--focus-ring-color);
      .react-aria-Input,
      .react-aria-Button {
        border-color: var(--focus-ring-color);
      }
    }
  }

  .react-aria-Button {
    font-size: 1.4rem;
    width: 2.3rem;
    padding: 0;
    display: inline-flex;
    align-items: center;
    justify-content: center;

    &[slot=decrement] {
      border-start-end-radius: 0;
      border-end-end-radius: 0;
    }

    &[slot=increment] {
      border-start-start-radius: 0;
      border-end-start-radius: 0;
    }
  }

  .react-aria-Input {
    background: var(--field-background);
    border: 1px solid var(--border-color);
    border-radius: 0;
    color: var(--field-text-color);
    margin: 0 -1px;
    z-index: 1;
    font-size: 1rem;
    padding: 0.429rem 0.571rem;
    outline: none;
    width: 6rem;
    flex: 1;
  }
}
```

</details>

## Features

Number fields can be built with `<input type="number">`, but the behavior is very inconsistent across
browsers and platforms, it supports limited localized formatting options, and it is challenging to style
the stepper buttons. `NumberField` helps achieve accessible number fields that support internationalized
formatting options and can be styled as needed.

* **Customizable formatting** – Support for internationalized number formatting and parsing including decimals, percentages, currency values, and units. Multiple currency formats are supported, including symbol, code, and name in standard or accounting notation.
* **International** – Support for the Latin, Arabic, Devanagari, Bengali, and Han positional decimal numbering systems in [over 30 locales](internationalization.html#supported-locales). The numbering system is automatically detected from user input, and input method editors such as Pinyin are supported.
* **Validation** – Keyboard input is validated as the user types so that only numeric input is accepted, according to the locale and numbering system. Values are automatically rounded and clamped according to configurable decimal, minimum, maximum, and step values. Custom client and server-side validation is also supported.
* **Mobile friendly** – An appropriate software keyboard is automatically selected based on the allowed values for ease of use.
* **Accessible** – Follows the [spinbutton](https://www.w3.org/WAI/ARIA/apg/patterns/spinbutton/) ARIA pattern, with support for arrow keys, scroll wheel, and stepper buttons to increment and decrement the value. Extensively tested across many devices and [assistive technologies](accessibility.html#testing) to ensure announcements and behaviors are consistent.

Read our [blog post](../blog/how-we-internationalized-our-numberfield.html) for more details about the interactions and internationalization support implemented by `NumberField`.

## Anatomy

<Anatomy />

Number fields consist of an input element that shows the current value and allows the user to type a new value,
optional stepper buttons to increment and decrement the value, a group containing the input and stepper buttons,
and a label.

`NumberField` also supports optional description and error message elements, which can be used
to provide more context about the field, and any validation messages. These are linked with the
input via the `aria-describedby` attribute.

```tsx
import {NumberField, Label, Group, Input, Button, Text, FieldError} from 'react-aria-components';

<NumberField>
  <Label />
  <Group>
    <Input />
    <Button slot="increment" />
    <Button slot="decrement" />
  </Group>
  <Text slot="description" />
  <FieldError />
</NumberField>
```

If there is no visual label, an `aria-label` or `aria-labelledby` prop must be passed instead
to identify the element to screen readers.

### Concepts

`NumberField` makes use of the following concepts:

<section className={styles.cardGroup} data-size="small">

<ExampleCard
  url="forms.html"
  title="Forms"
  description="Validating and submitting form data, and integrating with form libraries.">
  <Form />
</ExampleCard>

</section>

### Composed components

A `NumberField` uses the following components, which may also be used standalone or reused in other components.

<section className={styles.cardGroup} data-size="small">

<ExampleCard
  url="https://developer.mozilla.org/en-US/docs/Web/HTML/Element/label"
  title="Label"
  description="A label provides context for an input element.">
  <Label />
</ExampleCard>

<ExampleCard
  url="https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input"
  title="Input"
  description="An input allows a user to enter a plain text value with a keyboard.">
  <Input />
</ExampleCard>

<ExampleCard
  url="Button.html"
  title="Button"
  description="A button allows a user to perform an action.">
  <Button />
</ExampleCard>

</section>

## Starter kits

To help kick-start your project, we offer starter kits that include example implementations of all React Aria components with various styling solutions. All components are fully styled, including support for dark mode, high contrast mode, and all UI states. Each starter comes with a pre-configured [Storybook](https://storybook.js.org/) that you can experiment with, or use as a starting point for your own component library.

<StarterKits component="numberfield" />

## Reusable wrappers

If you will use a NumberField in multiple places in your app, you can wrap all of the pieces into a reusable component. This way, the DOM structure, styling code, and other logic are defined in a single place and reused everywhere to ensure consistency.

This example wraps `NumberField` and all of its children together into a single component which accepts a `label` prop, which is passed to the right place. It also shows how to use the `description` slot to render [help text](#description), and `FieldError` component to render [validation errors](#validation).

```tsx example export=true
import type {NumberFieldProps, ValidationResult} from 'react-aria-components';
import {Text, FieldError} from 'react-aria-components';

interface MyNumberFieldProps extends NumberFieldProps {
  label?: string,
  description?: string,
  errorMessage?: string | ((validation: ValidationResult) => string)
}

function MyNumberField({label, description, errorMessage, ...props}: MyNumberFieldProps) {
  return (
    <NumberField {...props}>
      <Label>{label}</Label>
      <Group>
        <Button slot="decrement"><Minus size={18} /></Button>
        <Input />
        <Button slot="increment"><Plus size={18} /></Button>
      </Group>
      {description && <Text slot="description">{description}</Text>}
      <FieldError>{errorMessage}</FieldError>
    </NumberField>
  );
}

<MyNumberField label="Cookies" />
```

## Value

### Controlled

By default, `NumberField` is uncontrolled. However, when using the `value` prop, it becomes controlled.
This allows you to store the current value in your own state, and use it elsewhere.

The `onChange` event is triggered whenever the number value updates. This happens when the user types a
value and blurs the input, or when incrementing or decrementing the value. It does not happen as the user
types because partial input may not be parseable to a valid number.

```tsx example
function Example() {
  let [value, setValue] = React.useState(6);

  return (
    <>
      <MyNumberField
        label="Controlled value"
        value={value}
        onChange={setValue} />
      <div>Current value prop: {value}</div>
    </>
  );
}
```

### HTML forms

NumberField supports the `name` prop for integration with HTML forms. The value will be submitted to the server as a raw number (e.g. `45`), not as a locale-dependent formatted string (e.g. `"$45.00"`).

```tsx example
<MyNumberField
  label="Transaction amount"
  /*- begin highlight -*/
  name="amount"
  /*- end highlight -*/
  defaultValue={45}
  formatOptions={{
    style: 'currency',
    currency: 'USD'
  }} />
```

## Number formatting

### Decimals

The default formatting style for `NumberField` is decimal, but you can configure various aspects via the `formatOptions`
prop. All options supported by [Intl.NumberFormat](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/NumberFormat/NumberFormat)
are supported, including configuration of minimum and maximum fraction digits, sign display, grouping separators, etc.
Currently only standard notation is supported, though scientific, engineering, and compact notation may be supported in the future.

The following example uses the `signDisplay` option to include the plus sign for positive numbers, for example to display
an offset from some value. In addition, it always displays a minimum of 1 digit after the decimal point, and allows up to
2 fraction digits. If the user enters more than 2 fraction digits, the result will be rounded.

```tsx example
<MyNumberField
  label="Adjust exposure"
  defaultValue={0}
  formatOptions={{
    signDisplay: 'exceptZero',
    minimumFractionDigits: 1,
    maximumFractionDigits: 2
  }} />
```

### Percentages

The `style: 'percent'` option can be passed to the `formatOptions` prop to treat the value as a percentage. In this mode,
the value is multiplied by 100 before it is displayed, i.e. `0.45` is displayed as `45%`. The reverse is also true: when the
user enters a value, the `onChange` event will be triggered with the entered value divided by 100. When the percent option
is enabled, the default step automatically changes to `0.01` such that incrementing and decrementing occurs by `1%`. This can
be overridden with the `step` prop. [See below](#step-values) for details.

```tsx example
<MyNumberField
  label="Sales tax"
  defaultValue={0.05}
  formatOptions={{
    style: 'percent'
  }} />
```

### Currency values

The `style: 'currency'` option can be passed to the `formatOptions` prop to treat the value as a currency value. The `currency`
option must also be passed to set the currency code (e.g. `USD`) to use. In addition, the `currencyDisplay` option can be
used to choose whether to display the currency symbol, currency code, or currency name. Finally, the `currencySign` option
can be set to `accounting` to use accounting notation for negative numbers, which uses parentheses rather than a minus sign
in some locales.

If you need to allow the user to change the currency, you should include a separate dropdown next to the number field.
The number field itself will not determine the currency from the user input.

```tsx example
<MyNumberField
  label="Transaction amount"
  defaultValue={45}
  formatOptions={{
    style: 'currency',
    currency: 'EUR',
    currencyDisplay: 'code',
    currencySign: 'accounting'
  }} />
```

### Units

The `style: 'unit'` option can be passed to the `formatOptions` prop to format the value with a unit of measurement. The `unit`
option must also be passed to set which unit to use (e.g. `inch`). In addition, the `unitDisplay` option can be used to choose
whether to display the unit in long, short, or narrow format.

If you need to allow the user to change the unit, you should include a separate dropdown next to the number field.
The number field itself will not determine the unit from the user input.

**Note:** the unit style is not currently supported in Safari. A [polyfill](https://formatjs.io/docs/polyfills/intl-numberformat/)
may be necessary.

```tsx example
<MyNumberField
  label="Package width"
  defaultValue={4}
  formatOptions={{
    style: 'unit',
    unit: 'inch',
    unitDisplay: 'long'
  }} />
```

## Validation

### Minimum and maximum values

The `minValue` and `maxValue` props can be used to limit the entered value to a specific range. The value will be clamped
when the user blurs the input field. In addition, the increment and decrement buttons will be disabled when the value is
within one `step` value from the bounds ([see below](#step-values) for info about steps). Ranges can be open ended by only
providing either `minValue` or `maxValue` rather than both.

If a valid range is known ahead of time, it is a good idea to provide it to `NumberField` so it can optimize the experience.
For example, when the minimum value is greater than or equal to zero, it is possible to use a numeric keyboard on iOS rather
than a full text keyboard (necessary to enter a minus sign).

```tsx example
<MyNumberField
  label="Enter your age"
  minValue={0} />
```

### Step values

The `step` prop can be used to snap the value to certain increments. If there is a `minValue` defined, the steps are calculated
starting from the minimum. For example, if `minValue={2}`, and `step={3}`, the valid step values would be 2, 5, 8, 11, etc. If no
`minValue` is defined, the steps are calculated starting from zero and extending in both directions. In other words, such that the
values are evenly divisible by the step. If no `step` is defined, any decimal value may be typed, but incrementing and decrementing
snaps the value to an integer.

If the user types a value that is between two steps and blurs the input, the value will be snapped to the nearest step. When
incrementing or decrementing, the value is snapped to the nearest step that is higher or lower, respectively.
When incrementing or decrementing from an empty field, the value starts at the `minValue` or `maxValue`, respectively, if defined.
Otherwise, the value starts from `0`.

```tsx example
<MyNumberField
  label="Step"
  step={10} />
<MyNumberField
  label="Step + minValue"
  minValue={2}
  step={3} />
<MyNumberField
  label="Step + minValue + maxValue"
  minValue={2}
  maxValue={21}
  step={3} />
```

### Validation errors

NumberField supports the `isRequired` prop to ensure the user enters a value, as well as custom validation functions, realtime validation, and server-side validation. It can also be integrated with other form libraries. See the [Forms](forms.html) guide to learn more.

To display validation errors, add a `<FieldError>` element as a child of the NumberField. This allows you to render error messages from all of the above sources with consistent custom styles.

```tsx example
import {Form, FieldError} from 'react-aria-components';

<Form>
  {/*- begin highlight -*/}
  <NumberField name="width" isRequired>
  {/*- end highlight -*/}
    <Label>Width</Label>
    <Group>
       <Button slot="decrement"><Minus size={18} /></Button>
       <Input />
       <Button slot="increment"><Plus size={18} /></Button>
     </Group>
    {/*- begin highlight -*/}
    <FieldError />
    {/*- end highlight -*/}
  </NumberField>
  <Button type="submit">Submit</Button>
</Form>
```

<details>
  <summary style={{fontWeight: 'bold'}}><ChevronRight size="S" /> Show CSS</summary>

```css
.react-aria-NumberField {
  &[data-invalid] {
    .react-aria-Input,
    .react-aria-Button {
      border-color: var(--invalid-color);
    }

    &:focus-within {
      .react-aria-Input,
      .react-aria-Button {
        border-color: var(--focus-ring-color);
      }
    }
  }

  .react-aria-FieldError {
    font-size: 12px;
    color: var(--invalid-color);
  }
}
```

</details>

By default, `FieldError` displays default validation messages provided by the browser. See [Customizing error messages](forms.html#customizing-error-messages) in the Forms guide to learn how to provide your own custom errors.

### Description

The `description` slot can be used to associate additional help text with a number field.

```tsx example
<NumberField>
  <Label>Width</Label>
  <Group>
    <Button slot="decrement"><Minus size={18} /></Button>
    <Input />
    <Button slot="increment"><Plus size={18} /></Button>
  </Group>
  {/*- begin highlight -*/}
  <Text slot="description">Enter a width in centimeters.</Text>
  {/*- end highlight -*/}
</NumberField>
```

<details>
  <summary style={{fontWeight: 'bold'}}><ChevronRight size="S" /> Show CSS</summary>

```css
.react-aria-NumberField {
  [slot=description] {
    font-size: 12px;
  }
}
```

</details>

## Disabled

The `isDisabled` prop can be used prevent the user from editing the value of the number field.

```tsx example
<MyNumberField label="Disabled" isDisabled value={25} />
```

<details>
  <summary style={{fontWeight: 'bold'}}><ChevronRight size="S" /> Show CSS</summary>

```css
.react-aria-NumberField {
  .react-aria-Button {
    &[data-disabled] {
      border-color: var(--border-color-disabled);
      color: var(--text-color-disabled);
    }
  }

  .react-aria-Input {
    &[data-disabled] {
      border-color: var(--border-color-disabled);
      color: var(--text-color-disabled);
    }
  }
}
  ```

</details>

### Read only

The `isReadOnly` prop makes the NumberField's value immutable. Unlike `isDisabled`, the NumberField remains focusable
and the contents can still be copied. See [the MDN docs](https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/readonly) for more information.

```tsx example
<MyNumberField label="Read only" isReadOnly value={32} />
```

## Props

### NumberField

<PropTable component={docs.exports.NumberField} links={docs.links} />

### Label

A `<Label>` accepts all HTML attributes.

### Group

A `<Group>` accepts all HTML attributes.

### Input

An `<Input>` accepts all props supported by the `<input>` HTML element.

### Button

A `<Button>` accepts its contents as `children`. Other props such as `onPress` and `isDisabled` will be set by the `NumberField`.

<details>
  <summary style={{fontWeight: 'bold'}}><ChevronRight size="S" /> Show props</summary>

<PropTable component={docs.exports.Button} links={docs.links} />

</details>

### FieldError

A `<FieldError>` displays validation errors.

<details>
  <summary style={{fontWeight: 'bold'}}><ChevronRight size="S" /> Show props</summary>

<PropTable component={docs.exports.FieldError} links={docs.links} />

</details>

## Styling

React Aria components can be styled in many ways, including using CSS classes, inline styles, utility classes (e.g. Tailwind), CSS-in-JS (e.g. Styled Components), etc. By default, all components include a builtin `className` attribute which can be targeted using CSS selectors. These follow the `react-aria-ComponentName` naming convention.

```css
.react-aria-NumberField {
  /* ... */
}
```

A custom `className` can also be specified on any component. This overrides the default `className` provided by React Aria with your own.

```jsx
<NumberField className="my-number-field">
  {/* ... */}
</NumberField>
```

In addition, some components support multiple UI states (e.g. focused, placeholder, readonly, etc.). React Aria components expose states using data attributes, which you can target in CSS selectors. For example:

```css
.react-aria-Button[data-pressed] {
  /* ... */
}
```

The `className` and `style` props also accept functions which receive states for styling. This lets you dynamically determine the classes or styles to apply, which is useful when using utility CSS libraries like [Tailwind](https://tailwindcss.com/).

```jsx
<Button className={({isPressed}) => isPressed ? 'bg-gray-700' : 'bg-gray-600'} />
```

The states, selectors, and render props for each component used in a `NumberField` are documented below.

### NumberField

A `NumberField` can be targeted with the `.react-aria-NumberField` CSS selector, or by overriding with a custom `className`. It supports the following states:

<StateTable properties={docs.exports.NumberFieldRenderProps.properties} />

### Label

A `Label` can be targeted with the `.react-aria-Label` CSS selector, or by overriding with a custom `className`.

### Group

A `Group` can be targeted with the `.react-aria-Group` selector, or by overriding with a custom `className`. It supports the following states:

<StateTable properties={docs.exports.GroupRenderProps.properties} />

### Input

An `Input` can be targeted with the `.react-aria-Input` CSS selector, or by overriding with a custom `className`. It supports the following states:

<StateTable properties={docs.exports.InputRenderProps.properties} />

### Button

A [Button](Button.html) can be targeted with the `.react-aria-Button` CSS selector, or by overriding with a custom `className`. Within a `NumberField`, there are two slots, which can be targeted with the `[slot=increment]` and `[slot=decrement]` CSS selectors. Buttons support the following states:

<StateTable properties={docs.exports.ButtonRenderProps.properties} />

### Text

The help text elements within a `NumberField` can be targeted with the `[slot=description]` and `[slot=errorMessage]` CSS selectors, or by adding a custom `className`.

### FieldError

A `FieldError` can be targeted with the `.react-aria-FieldError` CSS selector, or by overriding with a custom `className`. It supports the following render props:

<StateTable properties={docs.exports.FieldErrorRenderProps.properties} />

## Advanced customization

### Composition

If you need to customize one of the components within a `NumberField`, such as `Label` or `Input`, in many cases you can create a wrapper component. This lets you customize the props passed to the component.

```tsx
function MyInput(props) {
  return <Input {...props} className="my-input" />
}
```

### Contexts

All React Aria Components export a corresponding context that can be used to send props to them from a parent element. This enables you to build your own compositional APIs similar to those found in React Aria Components itself. You can send any prop or ref via context that you could pass to the corresponding component. The local props and ref on the component are merged with the ones passed via context, with the local props taking precedence (following the rules documented in [mergeProps](mergeProps.html)).

<ContextTable components={['NumberField']} docs={docs} />

This example shows a `FieldGroup` component that renders a group of number fields with a title. The entire group can be marked as read only via the `isReadOnly` prop, which is passed to all child number fields via the `NumberFieldContext` provider.

```tsx example
import {NumberFieldContext} from 'react-aria-components';

interface FieldGroupProps {
  title?: string,
  children?: React.ReactNode,
  isReadOnly?: boolean
}

function FieldGroup({title, children, isReadOnly}: FieldGroupProps) {
  return (
    <fieldset>
      <legend>{title}</legend>
      {/*- begin highlight -*/}
      <NumberFieldContext.Provider value={{isReadOnly}}>
      {/*- end highlight -*/}
        {children}
      </NumberFieldContext.Provider>
    </fieldset>
  );
}

<FieldGroup title="Dimensions" isReadOnly>
  <MyNumberField label="Width" defaultValue={1024} />
  <MyNumberField label="Height" defaultValue={768} />
</FieldGroup>
```

<details>
  <summary style={{fontWeight: 'bold'}}><ChevronRight size="S" /> Show CSS</summary>

```css
fieldset {
  padding: 1.5em;
  width: fit-content;
}
```

</details>

### Custom children

NumberField passes props to its child components, such as the label and input, via their associated contexts. These contexts are exported so you can also consume them in your own custom components. This enables you to reuse existing components from your app or component library together with React Aria Components.

<ContextTable components={['Label', 'Group', 'Input', 'Button', 'Text']} docs={docs} />

This example consumes from `LabelContext` in an existing styled label component to make it compatible with React Aria Components. The <TypeLink links={docs.links} type={docs.exports.useContextProps} /> hook merges the local props and ref with the ones provided via context by NumberField.

```tsx
import type {LabelProps} from 'react-aria-components';
import {LabelContext, useContextProps} from 'react-aria-components';

const MyCustomLabel = React.forwardRef((props: LabelProps, ref: React.ForwardedRef<HTMLLabelElement>) => {
  // Merge the local props and ref with the ones provided via context.
  ///- begin highlight -///
  [props, ref] = useContextProps(props, ref, LabelContext);
  ///- end highlight -///

  // ... your existing Label component
  return <label {...props} ref={ref} />;
});
```

Now you can use `MyCustomLabel` within a `NumberField`, in place of the builtin React Aria Components `Label`.

```tsx
<NumberField>
  {/*- begin highlight -*/}
  <MyCustomLabel>Value</MyCustomLabel>
  {/*- end highlight -*/}
  <Group>
    <Button slot="decrement"><Minus size={18} /></Button>
    <Input />
    <Button slot="increment"><Plus size={18} /></Button>
  </Group>
</NumberField>
```

### State

NumberField provides a <TypeLink links={statelyDocs.links} type={statelyDocs.exports.NumberFieldState} /> object to its children via `NumberFieldStateContext`. This can be used to access and manipulate the NumberField's state.

### Hooks

If you need to customize things even further, such as accessing internal state or customizing DOM structure, you can drop down to the lower level Hook-based API. See [useNumberField](useNumberField.html) for more details.
